Behind the scenes

Grebleips' species are a cameo appearance of the famous aliens of Steven Spielberg's 1982 film E.T. the Extra-Terrestrial. These creatures were inserted in the movie to make good on a promise—after Steven Spielberg included a Yoda cameo and Star Wars toys in E.T., George Lucas promised to include an E.T. cameo in the next Star Wars film he made—The Phantom Menace. While this is primarily an easter egg, and E.T. is probably not meant to be taken as part of Star Wars canon, some Star Wars references in E.T. can be reinterpreted in light of the E.T. references in Star Wars.

E.T.: The Book of the Green Planet reveals "Children of the Green Planet" to be the translated name of E.T.'s species. It also mentions several names which other alien species have given E.T.'s homeworld, such as Brodo Asogi, all of which translate to "Green Planet." While a species with the same name and appearance is itself part of Star Warscanon, and the homeworld name is given in Cloak of Deception, the species name is not specified.

When E.T. goes trick-or-treating with the children, he spots a child in a Yoda mask and begins to follow that child saying "Home… home…" (Composer John Williams included a snippet of his "Yoda Theme" from The Empire Strikes Back to accompany this scene.) This could be interpreted as E.T. recognizing a familiar species from his home galaxy.